Note: My intention is to take this series via the MIPS KVM tree, with a topic branch for the MIPS architecture changes, so acks welcome for the relevant parts (mainly patches 1-4, 15, 28), and please don't apply yet. This series primarily implements GVA->HPA page tables for MIPS T&E KVM implementation, and a fast TLB refill handler generated at runtime using uasm (sharing MIPS arch code to do this), accompanied by a bunch of related cleanups. There are several solid advantages of this: - An optimised TLB refill handler will be much faster than using the slow exit path through C code. It also avoids repeated guest TLB lookups for guest mapped addresses that are evicted from the host TLB (which are currently implemented as a linear walk through the guest TLB array). - The TLB refill handler can be pretty much reused in future for VZ, to fill the root TLB with GPA->HPA mappings from a soon to be implemented GPA page table. - Although not enabled yet, it potentially allows page table walker hardware (HTW) to be used during guest execution (both for VZ GPA mappings, and potentially T&E GVA mappings) further reducing TLB refill overhead. - It improves the robustness of direct access to guest memory by KVM, i.e. reading guest instructions for emulation, writing guest instructions for dynamic translation, and emulating CACHE instructions. This is because the standard userland memory accessors can be used, allowing the host kernel TLB refill handler to safely fill from the GVA page table, allowing faults to be sanely detected, and allowing it to work when EVA is enabled (which requires different instructions to be used when accessing the user address space). The main disadvantage is a higher flushing overhead when the guest ASID is changed, due to the need to walk and invalidate GVA page tables (since we only manage a single GVA page table for each guest privilege mode, across all guest ASIDs). The patches are roughly grouped as follows: Patches 1-4: These are generic or MIPS architecture changes needed by the later patches, mainly to expose the existing MIPS TLB exception generation cade to KVM. As I mentioned above I intend to combine the MIPS ones into a topic branch which can be merged into both the MIPS architecture tree and the MIPS KVM tree. Patches 5-13: These are preliminary MIPS KVM changes and cleanups. Patches 14-25: These incrementally add GVA page table support, allocating the GVA page tables, adding the fast TLB refill handler, addng page table invalidation, and finally converting guest fault handling (KSeg0, TLB mapped, and commpage) to use the GVA page table rather than injecting entries directly into the host TLB. Patches 26-27: These switch to using uaccess and protected cache ops, which fixes KVM on EVA enabled host kernels. Patches 28-30: These make some final cleanups. Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: "Radim Krčmář" <rkrcmar@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Cc: kvm@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx James Hogan (30): mm: Export init_mm for MIPS KVM use of pgd_alloc() MIPS: Export pgd/pmd symbols for KVM MIPS: uasm: Add include guards in asm/uasm.h MIPS: Export some tlbex internals for KVM to use KVM: MIPS: Drop partial KVM_NMI implementation KVM: MIPS/MMU: Simplify ASID restoration KVM: MIPS: Convert get/set_regs -> vcpu_load/put KVM: MIPS/MMU: Move preempt/ASID handling to implementation KVM: MIPS: Remove duplicated ASIDs from vcpu KVM: MIPS: Add vcpu_run() & vcpu_reenter() callbacks KVM: MIPS/T&E: Restore host asid on return to host KVM: MIPS/T&E: active_mm = init_mm in guest context KVM: MIPS: Wire up vcpu uninit KVM: MIPS/T&E: Allocate GVA -> HPA page tables KVM: MIPS/T&E: Activate GVA page tables in guest context KVM: MIPS: Support NetLogic KScratch registers KVM: MIPS: Add fast path TLB refill handler KVM: MIPS/TLB: Fix off-by-one in TLB invalidate KVM: MIPS/TLB: Generalise host TLB invalidate to kernel ASID KVM: MIPS/MMU: Invalidate GVA PTs on ASID changes KVM: MIPS/MMU: Invalidate stale GVA PTEs on TLBW KVM: MIPS/MMU: Convert KSeg0 faults to page tables KVM: MIPS/MMU: Convert TLB mapped faults to page tables KVM: MIPS/MMU: Convert commpage fault handling to page tables KVM: MIPS: Drop vm_init() callback KVM: MIPS: Use uaccess to read/modify guest instructions KVM: MIPS/Emulate: Fix CACHE emulation for EVA hosts KVM: MIPS/TLB: Drop kvm_local_flush_tlb_all() KVM: MIPS/Emulate: Drop redundant TLB flushes on exceptions KVM: MIPS/MMU: Drop kvm_get_new_mmu_context() arch/mips/include/asm/kvm_host.h | 76 ++-- arch/mips/include/asm/mmu_context.h | 9 +- arch/mips/include/asm/tlbex.h | 26 +- arch/mips/include/asm/uasm.h | 5 +- arch/mips/kvm/dyntrans.c | 28 +- arch/mips/kvm/emulate.c | 59 +-- arch/mips/kvm/entry.c | 141 +++++++- arch/mips/kvm/mips.c | 130 +------ arch/mips/kvm/mmu.c | 545 +++++++++++++++++------------ arch/mips/kvm/tlb.c | 225 +----------- arch/mips/kvm/trap_emul.c | 220 +++++++++++- arch/mips/mm/init.c | 1 +- arch/mips/mm/pgtable-32.c | 1 +- arch/mips/mm/pgtable-64.c | 3 +- arch/mips/mm/tlbex.c | 38 +- mm/init-mm.c | 2 +- 16 files changed, 861 insertions(+), 648 deletions(-) create mode 100644 arch/mips/include/asm/tlbex.h -- git-series 0.8.10 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
